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Festool. Their bits are somewhat hidden. You have to go to the product pages for the routers and then look at their accessories. Try the 1010 watt router accessories to start. Here are some product IDs that might help:
Arbors for Slot Cutters: 491061, 491062
Slot cutters: 491038 (1.5mm), 491039 (1.8mm)
Flush trim: 491027, 491028
Chamfer: 491024, 491025, 491132, 491133
You can search for these product IDs and they should take you directly to the product page. I didn't see a 1.6mm bit, but 1.5mm should work. The 1.5mm bit will cut the slot .0034" too small, which isn't much. I think the last piece of paper I measured with a micrometer was .0050" or .0100"